A few weeks ago, many customers feedback that there is a kind of attack from internet, it used telnet serivce frequently to login the inrouter which has public IP address, this attack could waste a lot data flow of cellular interface or leads to inrouters restore the factory settings, so here we give some suggestions to avoid this kind of attack:

1.If you didn't use telnet service or other management services, you'd better disable them inrotuer, use https to replace http service;